Many studies have shown the negative consequences that overweight and obesity can have on the health of the pregnant woman and the developing fetus, since excess weight can cause or aggravate pregnancy complications such as preeclampsia or gestational diabetes , among other.

However, thin women, and especially those with a body mass index (BMI) less than 18.5, can also have a risky pregnancy, because of a complication known as oligohydramnios, which consists of the shortage of amniotic fluid, usually occurs at the end of pregnancy, and increases the risk of the baby being born dead or having to be admitted to the ICU.

Very thin women have a higher risk of suffering from oligohydramnios, a disorder that consists of a shortage of amniotic fluid

The Virgen de las Nieves University Hospital of Granada has carried out a study, which has involved the participation of 3,016 pregnant women, of whom 5.5% were very thin, which has revealed that these are more likely to suffer oligohydramnios. While in the general population this complication has an incidence of approximately 3%, in the studied group it affected 8.3% of excessively thin, 3.6% of those with normal weight, and 4.4 % of those who were obese.

Oligohydramnios can occur for various reasons, such as the fetus urinating little, or the amniotic fluid is lost as a result of ruptured membranes. In the case of women who participated in the study and presented low weight, the researchers explained that very thin women usually eat little, so the fetus does not eat enough and barely urinates. As the amount of amniotic fluid depends on the urine of the fetus, it decreases, and becomes insufficient.

Dr. Sebastian Manzanares, who has directed the research, warns that when the pregnant woman is very thin, controls should be maximized during pregnancy to monitor the growth of the fetus and the possible decrease in amniotic fluid, especially in the third trimester of pregnancy. pregnancy. The specialist points out that, in addition, it is necessary to insist that these women have a balanced diet during pregnancy, whose energy intake does not drop 1,500 calories a day, and take iron supplements and vitamins when necessary.

2nd Trimester Q&A with Belly to Baby (November 2019).