Résumé
Background: In India, teenage pregnancy is an important public-health problem, although the national policy of the Government of India advocates the minimum legal age of marriage for girls to be 18 years. Data of the National Family Health Survey (NFHS)-3 revealed that 16% of women, aged 15-19 years, have already started childbearing. Teenage pregnancies represent a high-risk group in reproductive terms because of the double burden of reproduction and growth. Complications of pregnancy and childbirth are the leading cause of mortality among girls aged 15-19 years in developing countries. Aim and objective of the study was to study the prevalence of teenage pregnancies and to study the clinic social impact of teenage pregnancies.Methods: The observational cross-sectional study was conducted in Government General Hospital, Guntur in the department of Obstetrics and Gynaecology over three Months from August to October 2018. All pregnant women coming to either OPD or directly to the labour room were included in the study group. History was taken and examination was done.Results: Among the 709 deliveries in the institute, 138 are teenage pregnancies contributing to 19.4%. Prevalence of anaemia in teenage mothers is as high as 63.7%, pregnancy induced hypertension contributing to 26.8% and abortions 9.4%. The neonatal outcome is poor in teenage mothers, low birth weight 20.2% contributing to the main morbidity.Conclusions: Teenage pregnancy is associated with an increased incidence of preeclampsia, eclampsia, preterm delivery, increased incidence of instrumental deliveries and lower segment caesarean sections due to cephalopelvic disproportion, neonatal complications, increased neonatal morbidity and mortality mainly due to low birth weight was noted in babies delivered to teenage mothers.
Résumé
In the vegetative cells of heterocystous cyanobacteria, such as Anabaena, two Operons harbouring the nitrogen fixation (nif) genes contain two separate intervening DNA elements resulting in the dispersion of genes and impaired gene expression. A 11 kb element disrupts the nifD gene in the nifH, D-K operon. It contains a 11 bp sequence (GGATTACTCCG) directly repeated at its ends and harbours a gene, xisA, which encodes a site-specific recombinase. A large 55 kb element interrupts the fdxN gene in the nifB fdxN-nifS-nifU operon. It contains two 5 bp direct repeats (TATTC) at its ends and accommodates at least one gene, xisF, which encodes another site-specific recombinase. During heterocyst differentiation both the discontinuities are precisely excised by two distinct site-specific recombination events. One of them is brought about by the XisA protein between the 11 bp direct repeats. The second one is caused by the XisF protein and occurs between the 5 bp direct repeats. As a consequence the 11kb and 55 kb elements are removed from the chromosome as circles and functional nif Operons are created. Nitrogenase proteins are then expressed from the rearranged genes in heterocysts and aerobic nitrogen fixation ensues. How these elements intruded the nif genes and how and why are they maintained in heterocystous cyanobacteria are exciting puzzles engaging considerable research effort currently. The unique developmental regulation of these gene rearrangements in heterocystous cyanobacteria is discussed.