Intergenerational effects of in utero exposure to Ramadan in Tunisia.

UNLABELLED: We have reported that changes in the lifestyle of pregnant women during Ramadan affect more than one generation. In a series of newborn babies in Saudi Arabia, those whose mothers had been in utero during Ramadan differed from those whose mothers had not been in utero during Ramadan. These were unexpected findings and require replication. METHODS: We examined body size at birth in 1,321 babies (682 boys and 639 girls) born in Gafsa, a small city in Tunisia. RESULTS: Babies whose mothers had been in utero during Ramadan were smaller and thinner, and had smaller placentas, than those whose mothers had not been in utero during Ramadan. After adjustment for sex, the babies were 93 g lighter (95% confidence interval, 32-153, P=0.003) than those whose mother had not been in utero during Ramadan, their mean ponderal index was 0.52 kg/m(3) lower (0.24-0.79, P<0.001) and their placental weight was 21 g lower (5-37, P=0.01). The findings did not differ by trimester of maternal exposure to Ramadan. They were similar in boys and girls and in primiparous and multiparous mothers CONCLUSION: This study provides further evidence that changes in lifestyle during Ramadan have intergenerational effects.

The breadth of the placental surface but not the length is associated with body size at birth.

Studies of pregnancies complicated by preeclampsia led to the suggestion that the surface of the placenta is aligned along two axes, measured by its breadth and length. It was hypothesised that tissue along the breadth serves as a nutrient sensor, responding to the mother's nutritional state and fetal nutritional demands, while tissue along the length has different functions. To develop this hypothesis we measured the breadth and length of the placental surface in 401 neonates born in the King Khalid Hospital, Riyadh, Saudi Arabia, and related these measurements to the baby's body size. The breadth and length of the placental surface were highly correlated (coefficient = 0.7). Nevertheless, in a simultaneous regression with both measurements, only the breadth was associated with neonatal body size. There were strong trends of increasing birth weight, ponderal index, and the circumferences of the head, chest, abdomen and thigh with increasing placental breadth. In contrast no measurement of baby's body size was related to placental length. Birth weight increased by 125 g per cm increase in placental breadth (95% confidence interval 88 to 162, p < 0.001) but only by 20 g per cm increase in placental length (-13 to 53, p = 0.2). The corresponding figures for head circumference were 0.28 cm (0.17-0.39, p < 0.001) and 0.03 (-0.07 to 0.14, p = 0.5). The associations between placental breadth and neonatal body size were strongest if the mother's height was below the median (157 cm). The associations between a larger breadth of the placental surface and a larger baby are consistent with the hypothesis that tissue along the breadth plays a key role in nutrient transfer from mother to baby. Mothers who are short in stature are known to have lower rates of protein turnover in pregnancy. In these circumstances the ability of the placenta to transfer amino acids to the fetus may be critical.

Sex differences in birth size and intergenerational effects of intrauterine exposure to Ramadan in Saudi Arabia.

OBJECTIVES: In Europe, boys and girls have different body proportions at birth. We examined newborn babies in Saudi Arabia to determine the sex differences and whether fetal growth differed if the mother was in utero during Ramadan. METHODS: We examined body size at birth among 967 babies (479 boys and 488 girls) born in Unizah, a small city in Saudi Arabia. RESULTS: Large head circumference was the strongest single predictor of male sex. In a simultaneous regression, female sex was predicted by small head circumference (P < 0.001), low birth weight (P = 0.002), and large chest circumference (P = 0.008). The mothers of boys were heavier in pregnancy than the mothers of girls and had a higher body mass index, 31.7 kg/m(2) compared to 30.2 (P < 0.001). The mothers of girls, however, were taller than the mothers of boys, 158.6 cm compared to 157.4 (P = 0.001). Compared to babies whose mothers were not in utero during Ramadan boys whose mothers were in mid gestation during Ramadan were 1.2 cm longer (P = 0.005) while girls had a 0.4 week shorter gestation period (P = 0.04). CONCLUSION: Our findings are consistent with other evidence that boys are more ready than girls to trade off visceral development in utero to protect somatic and brain growth. They also support the hypothesis that boys are more responsive to their mother's current diet than girls, who respond more to their mother's life time nutrition and metabolism. They provide the first evidence that changes in the life style of pregnant women during Ramadan affect more than one generation.

Secular increase in placental weight in Saudi Arabia.

BACKGROUND: Ramadan is an annual period of day-time fasting during which people in Saudi Arabia, including pregnant women, change their diets and physical activity. We recently reported that among babies who were in the second or third trimester of gestation during Ramadan placental growth slowed. We also found that, over the four years of the study, placental weight increased by 29 g per year. We have now extended our data collection in order to examine this trend in more detail. METHODS: We studied the birth records of 17 660 singletons born in King Saud Hospital, Unizah, Saudi Arabia, over a ten year period. The records included birth weight, placental weight and gestational age. RESULTS: During the first six years of the study period mean placental weight rose by more than 100 g while mean birth weight was unchanged. This secular increase in placental weight was accompanied by a change in the placenta's response to Ramadan. During the first half of the study period babies who were in their second or third trimester of gestation during Ramadan had reduced placental weight (475 g and 476 g compared with 484 g, p < 0.001 for both). During the second half of the study period babies who were in their first trimester of gestation during Ramadan had reduced placental weight (533 g compared with 539 g, p = 0.03). CONCLUSIONS: We suggest that the secular increase in placental weight reflects changes in maternal body composition. These have altered placental responses to the dietary changes during Ramadan. The biological processes underlying these responses are not known.

Changes in placental size during Ramadan.

BACKGROUND: Placental growth responds to maternal influences. Ramadan is an annual period of day-time fasting during which people in Saudi Arabia, including pregnant women, change their diets and physical activity. Little is known about the effects of this altered lifestyle on placental development. METHODS: We studied the birth records of 7083 babies born over a four-year period to Saudi nationals in Unizah, a small city 350km to the north of Riyadh, the capital city of Saudi Arabia. The records included birth weight, placental weight and gestational age. RESULTS: Mean birth weight was similar to European values but the mean placental weight and ratio of placental weight to birth weight were lower. Among babies who were in the second or third trimester of gestation during Ramadan the mean placental weight and ratio were below those of babies who were not in utero during Ramadan. Among boys the mean placental ratios were 14.4 percent (second trimester) and 14.5 percent (third trimester) compared with 14.9 percent (p=<0.001 and 0.002). The corresponding figures for girls were 14.8 and 14.6 percent compared with 15.1 percent (p=0.02 and <0.001). CONCLUSIONS: In Saudi Arabia placentas respond to mothers' limited ability to deliver nutrients to them. Placental growth slows but efficiency is increased so that fetal growth is sustained, albeit with a reduced reserve capacity. The lifestyle changes associated with Ramadan further slow placental growth. Ramadan may influence placental growth through dietary changes other than day-time fasting. Changes in placental growth during Ramadan could be associated with altered fetal programming, and may therefore have long-term implications for the health of the next generation.