Vilma has this to say in response to my question... Vilma -- anything to say about multiple close pregnancies in women??
There is a slightly higher risk of complications w/ closely spaced pregnancies, but actually not dramatically higher. Bleeding, anemia, nutrition issues mostly. Risk of poor nutrition to fetus if mom is still breast feeding the last baby. Maternal exhaustion!! :-) But multiple pregnancies in general (independent of timing/spacing) IS actually fairly strongly associated w/ increased risk of uterine atony (poor contraction of the uterine muscle) after delivery resulting in significant post partum hemorrhage immediately after delivery. The problem is it is hard to study this in people carefully. Most of the time there are also coexisting socioeconomic factors or increasing maternal age (both of which will strongly increase risk of complications such as preeclampsia, hemorrhage, hypertension, premature delivery, poor intrauterine growth) that come in to play more than the timing of the pregnancies alone in humans. In humans, the risks increase most dramatically w/ 5 or more deliveries and "reproductive age" is considered 15-45 yrs old, with the highest risks in patients 15 or younger and 35 or older. Vilma Briggs, MD (OB/GYN) Ohio