Nanometer scale polarimetry studies using a near-field scanning optical microscope.

We describe a new technique that incorporates polarization modulation into near-field scanning optical microscopy (NSOM) for nanometer scale polarimetry studies. By using this technique, we can quantitatively measure the optical anisotropy of materials with both the high sensitivity of dynamic polarimetry and the high spatial resolution of NSOM. The magnitude and relative orientation of linear birefringence or linear dichroism are obtained simultaneously. To demonstrate the sensitivity and resolution of the microscope, we map out stress-induced birefringence associated with submicrometer defects at the fusion boundaries of SrTiO3 bicrystals. Features as small as 150 nm were imaged with a retardance sensitivity of approximately 3 x 10(-3) rad.

Steroid contraceptive use and pregnancy outcome.

Contraceptive use in relation to pregnancy outcome was studied in 8,816 births in Chiang Mai, northern Thailand, by examination of newborn infants and interviews with their mothers. Four thousand twenty-three women used no contraception before the index pregnancy, 1,229 used the injectable contraceptive Depo Provera (DMPA), and 3,038 used oral contraceptives prior to or during pregnancy. No differences were observed between these groups with respect to still births, multiple pregnancies, and birthweight. Women who used oral contraceptives had unexpectedly low rates of major defects and may have been affected by self-selection bias, whereas the noncontraceptors had rates similar to other populations. There was a significantly increased association of polysyndactyly among infants of DMPA users relative to the other groups, which was most pronounced in offspring of women under age 30 years, and persisted after exclusion of subjects with a family history or infants with multiple abnormalities. However, in five out of the ten polysyndactyly cases, the last injection of DMPA occurred more than 9 months before conception, and only three cases had definite gestational exposure. The association of chromosomal anomalies was also significantly increased in infants of mothers who used DMPA. The unrelated nature of these defects, the lack of confirmation from other studies, the distant preconceptional exposure to DMPA in many cases, and chance effects due to multiple statistical comparisons make a causal association unlikely. Other birth defects that had been previously reported in some publications to be associated with progestational steroid exposure, such as neural tube defects, heart malformations, and limb reduction defects, were not found in this study.(ABSTRACT TRUNCATED AT 250 WORDS)

The use of quinesterol for the control of vaginal bleeding irregularities caused by DMPA.

A comparative clinical trial examined the effect of oral administration of a long-acting estrogen (quinesterol) on the vaginal bleeding pattern of 214 Thai women receiving 3 monthly injections of the contraceptive depot-medoxyprogesterone acetate. Although the proportion of subjects with amenorrhea was lower in the group receiving quinesterol, there was no substantial increase in the proportion of women with normal bleeding patterns.

PIP: In a double-blind clinical trial the effect on the bleeding pattern disrupted by progesterone-only injectable contraception of quinestrol, an estrogen which is stored in body fat and is slowly released over days, was studied in 236 Thai women giving informed consent and having irregular or nonexistent bleeding patterns since the start of Depo-Provera contraception. In all 214 women participated in the complete trial, receiving 3 monthly injections of depot-medroxyprogesterone acetate. The bleeding pattern showed no statistical significance between the quinestrol-treated group and placebo group in terms of the overall effects on the following definitions: acceptable bleeding, amenorrhea, irregular bleeding and prolonged bleeding. However, there was an apparent increase in amenorrhea in the placebo group after the second injection of progestin as well as a fall in irregular bleeding. Prolonged bleeding was seen most frequently after the first injection, and declined during the later injection study periods. Acceptable bleeding occurred in only 6 of 78 subjects in the fourth injection group. Hence, the use of quinestrol in this trial did not significantly change the bleeding pattern of depot-medroxyprogesterone acetate users.

Return of fertility after discontinuation of depot medroxyprogesterone acetate and intra-uterine devices in Northern Thailand.

796 Thai women who stopped using the long-acting injectable contraceptive 'Depo-Provera' (medroxyprogesterone acetate) and 125 women who had an intra-uterine device removed to have a planned pregnancy were followed-up to ascertain the delay between conception and the end of contraception, and to determine the proportion of women who did not conceive in the 2 years after discontinuation. The median delay before conception was 5.5 months plus the estimated duration of the effect of the last injection of depo-provera and 4.5 months after discontinuing the IUD. Since depo-provera acts for approximately 15 weeks, women can except a median delay to conception of around 9 months after their last injection. The proportions of women who did not conceive within 1 year and within 2 years of stopping contraception by the two methods were similar. There was no evidence to suggest that prolonged use of depo-provera increases the delay before conception, and the return of fertility among never pregnant ex-users resembled that of ever pregnant ex-users.

PIP: 796 Thai women (from the family planning clinic of the McCormick Hospital in Chiang Mai, Northern Thailand) who discontinued use of DMPA (depot medroxyprogesterone acetate) and 125 women who stopped using IUD to have a planned pregnancy were followed up to determine the proportion of women who did not conceive within 2 years of discontinuation, and to ascertain the delay between conception and end of contraception. The study was divided into 2 groups: retrospective (consisting of women who discontinued contraception before 12/74 to become pregnant) and prospective (those who stopped DMPA for aplanned pregnancy between 1/75 and 12/76. Life-table conception rates and standard errors were estimatedat monthly intervals and cumulatively over time; median delay before conception was calculated from cumulative rates. As both prospective and retrospective groups exhibited similar cumulative proportions conceiving, the 2 groups were combined for simplicity of presentation of data. Median delay before conception was found to be 5.5 months plus the estimated duration of the effect of the last injection of DMPA and 4.5 months after IUD discontinuation. As the effect of DMPA lasts for approximately 15 weeks, a median delay to conception of around 9 months after last injection can be expected. The proportion of women who did not become pregnant within 1 year and within 2 years of discontinuation of contraception was similar for both methods (DMPA: 21.8% at 1 year and 7.9% at 2 years; IUD: 21% at 1 year and 6.7% at 2 years). Prolonged use of DMPA also did not increase delay before conception, and return of fertility among never pregnant ex-users was similar to that of ever pregnant ex-users.

Extracts from the report on the Joint IGCC/IFRP East and South East Asia Seminar on Regional Fertility Research.

PIP: The attempt is made to provide some answers on the use of Depo Provera. In the use of Depo Provera, the standard procedure is to give an injection of 150 mgs in 1 ml in an arm or hip muscle every 12 weeks, beginning soon after delivery or miscarriage or early in the menstrual cycle in the case of menstruating women. The outstanding attraction of the long-acting contraceptive injection in the minds of the 81,034 Chiang Mai acceptors is what can be described as the freedom from the fear of forgetting. The acceptors also enjoyed the ease and convenience of administration and the high effectiveness of the method. Of 142 women using this method for a year, on an average, only one woman will have an unexpected pregnancy. Depo Provera has a lower failure rate then IUDs, condoms, foams, jellies, or the "safe period," and it does not produce pelvic infection and inflammation wometimes seen with IUDs. It also does not effect breast milk in nursing mothers. The drawbacks to the use of the injectable contraceptive include amenorrhea, irregular menstrual periods, spotting, and sometimes heavy periods. Depo Provera also has other uses which include use in instances of threatened and habitual miscarriage and use in the treatment of endometriosis. Depo Provera is a safe method. Among the estimated 1 million or so users, there has not been a death caused by Depo Provera. Depo Provera has been approved for use in 10 European countries. The World Health Organization and the International Planned Parenthood Federation have approved the use of Depo Provera.^ieng

Endometrial carcinoma survey in Thailand.

PIP: The McCormick Hospital's Family Planning program in Chiang Mai, Thailand surveyed all admissions to the hospital for carcinoma of the endometrium in light of the discovery by the Upjohn Company that 2 monkeys had developed endometrial carcinoma when given 50x the dosage of Depo-Provera. Chiang Mai and Lumpoon provinces were the targets of this survey since these are the 2 areas where Depo-Provera was widely used and where 35,000 women were current users. 16 of the 25 recorded cases hailed from these 2 provinces and 6 were eliminated from this examination. There has been no increase in the recorded incidence of endometrial carcinoma despite the widespread use of Depo-Provera (a total of 86,511 women; 864,492 injections; usage experience of 207,694 women-years; and more than 300 women who have been using the drug for 10-13 years). In 1978, there was actually a lower recorded incidence than in the 3 years prior. Thus the Upjohn data (using 50x the human dosage level for 10 years) should not be applied to women on normal doses of Depo-Provera. Also, long-term use of these injections can be continued without concern about developing endometrial carcinoma.^ieng

International forum update: depot medroxyprogesterone acetate and endometrial carcinoma.

In response to a recent report (Fam Plann Perspect 11: 47, 1979) that two of 12 rhesus monkeys given 50 times the human dose of depot medroxyprogesterone acetate (DMPA), by body weight, for ten years had developed endometrial carcinoma (CA), a retrospective survey of all hospital admissions for proven endometrial CA in two Thai provinces where DMPA contraceptive injections have been widely used since 1965 was made. From 1974 through 1978, 16 women were hospitalized with confirmed diagnoses of endometrial CA. None of the nine women successfully followed up had previously used oral or injectable contraceptives, nor has the recorded incidence of endometrial CA increased in these provinces. Base on the available evidence, the authors conclude that (a) the data on monkeys given very large doses of DMPA for ten years do not apply to women given normal doses of DMPA for prolonged periods and (b) widespread and long-term use of DMPA can and should be continued.

Use of nurse-midwives for minilap sterilization.

PIP: A pilot research study was conducted at the Chiang Mai Christian Clinic of the McCormick Hospital's Family Planning Program in northern Thailand from August 1976-78. 450 cases of minilap performed by 2 surgical-theatre nurses were compared to 450 cases performed by a physician-surgeon, working with the same socioeconomic class of patients, in the same location, under the same circumstances. The training course for operating-theater nurse-surgeons took 3 steps: 1) long experience as an operating theater nurse in general surgery, followed by long experience in assisting minilaps; 2) 2-week intensive training in which nurse performs approximately 15 minilaps with physician assisting; and, 3) performance of minilap by the nurse as first surgeon. To date, each of the 2 theater nurse-surgeons has performed about 225 minilap sterilizations as first surgeon. Hematomas of the wound occurred largely in the early experience of the nurse surgeons. Perforation of the uterus with the uterine elevator occurred in 3 physician-surgeon cases, 1 in the nurse-surgeon cases. This is attributed to the more difficult cases assigned to the physician-surgeons. In the physician-surgeon group there was 1 case of urinary bladder injury, due to a previous Caesarean section with extensive adhesions. All operations were performed on an outpatient basis under local anaesthesia after premedication with diazapam and atropine.^ieng

The timing of the first injection of Depo Provera.

PIP: The timing of the 1st injection of the contraceptive Depo Provera was studied by examining the risk of accidental pregnancy during 3 months following the 1st injection in 7930 women. The pregnancy rate was 1.62 pregnancies/1000 women if the injection was given within the 1st 8 days of the cycle and 6.22 pregnancies/100 women if given between cycle day 9 and 28. The difference is statistically significant (p less than .01). It is recommended that women who present later than cycle day 7 for an injection be given additional contraceptive protection for at least 1 month. There is no justification for rejecting a woman if she requests an injection at any time during her menstrual cycle.^ieng

Use-effectiveness of six-month injections of DMPA as a contraceptive.

PIP: The use of depot-type injections of the contraceptive medroxyprogesterone acetate (DMPA) was studied in 1132 women for up to 5 1/2 years. Continuation rates, reasons for discontinuation, method failure rates, and bleeding patterns were considered. The women received a dose of 400 mg DMPA in aqueous suspension (injected into the deltoid muscle) every six months. In addition, each patient received an oral dose of .04 mg ethynl estradiol for 10 days each lunar month. Of the original acceptors, 36.4 percent used the method for the full 5 1/2 years. The major reasons for discontinuation of DMPA injections were bleeding problems (including amenorrhea) and such other medical reasons as palpitation, abdominal pain, headache, weakness, and dizziness. A total of 26 women became accidently pregnant while using DMPA during the 5 1/2 years. Advantages of DMPA injections were the simplicity, safety, and effectiveness of the method, and the psychological appeal of an injectable contraceptive.^ieng

Use of a long-acting injectable contraceptive in a postpartum family planning program.

PIP: A study of intramuscular injections of depo medroxyprogesterone acetate (Depo Provera) as a postpartum contraceptive was undertaken in an attempt to determine the following: 1) the continuation rates for this contraceptive method in a postpartum family planning program; 2) to compare the continuation rates of Depo Provera given as a postpartum contraceptive with other postpartum contraceptive methods, as reported elsewhere; 3) the use-effectiveness of Depo Provera as a postpartum contraceptive method; 4) the side effects of postpartum injections; and 5) the reasons for discontinuation of this method. Between April 1969 and May 31, 1972 there were a total of 325 acceptors at the Family Planning Department of McCormick Hospital in Chiang Mai, Thailand. 217 of the women were acceptors of 3-month injections and 108 women were acceptors of 6-month injections. Of all acceptors, 94.2% received their 1st injection within 5 days of delivery. Cases continuing beyond 12 months were too few in number for significant statistical analysis. There were no known method failure pregnancies. Of the 325 postpartum acceptors of the 3-month and 6-month Depo Provera injections, 152 had discontinued the method by May 31, 1972. Of these, 47 were lost to follow up. The reasons for the discontinuation of the 105 remaining cases were bleeding problems (amenorrhea, prolonged, frequent or heavy bleeding, and irregular periods), other medical reasons (palpitation and dizziness, abdominal pain, pain at injection site, and melasma), and personal reasons.^ieng