By Lauren Hasz from Healthline
Among the many changes that occur during the perinatal time (pregnancy and up to the first year postpartum), a mother’s normal blood pressure is altered to support the work her body is accomplishing. While slight alteration is expected, anything too high or too low can indicate a potential health problem for mother and/or baby.
What is normal?
During the early weeks of pregnancy, blood pressure may drop slightly, giving mothers a lightheaded feeling on occasion (Planck, 2009). According to Nina Planck, author of “Real Food for Mother and Baby,” orthostatic hypotension or “temporary low blood pressure on standing upright” (p. 89) in pregnancy can occur as pregnancy hormones relax blood vessels to make space for extra blood before the actual blood has been created. In contrast, most of pregnancy is often characterized by slightly elevated blood pressure levels that reflect the greater blood volume needed to support both mom and baby (Planck, 2009).
A little high is a good thing!
According to Dr. Michel Odent, a French obstetrician and childbirth specialist, “An isolated increased blood pressure is usually a good sign of placental activity. The placenta – as the advocate of the baby – manipulates maternal physiology via the release of hormones and asks the mother to provide more blood” (as cited in Planck, 2009).
As succinctly summarized by the BabyCentre Medical Advisory Board (2013), blood pressure often falls during first and second trimester, reaching its lowest point around 23 weeks pregnant. From about 24 weeks pregnant until a few weeks before delivery, blood pressure slowly rises, as more blood is pumped throughout the body and to the baby via the placenta. After delivery, blood pressure levels should return to normal levels within a couple of weeks.
When to worry?
Why then do healthcare providers so carefully record blood pressure levels at each prenatal visit? While it is absolutely true that a mama’s body adapts to pregnancy in superhuman fashion, it is also true that occasionally complications arise that could harm a mama’s and baby’s health.
According to Healthline, gestational hypertension is diagnosed when a mama has higher than normal blood pressure after 20 weeks of pregnancy. This is in contrast to chronic hypertension, which is elevated blood pressure before pregnancy that continues through all trimesters. Although rarely fatal, both gestational and chronic hypertension diagnoses do increase a mother’s chances of developing preeclampsia or eclampsia later in pregnancy, and therefore intervention.
According to the American Pregnancy Association, this elevated blood pressure (over 140/90) affects between 6-8% of pregnant women and can have serious repercussions if not treated (2014).
“Hypertension can prevent the placenta from getting enough blood. If the placenta doesn’t get enough blood, your baby gets less oxygen and food. This can result in low birth weight,” (American Pregnancy Association, 2014).
Although there are no guaranteed ways to prevent gestational hypertension, a health-minded mama can make sure that she is salting foods to taste, drinking plenty of water, increasing protein intake, resting, exercising, elevating her feet, avoiding alcohol, and avoiding caffeine (American Pregnancy Association, 2014).
If hypertension becomes an issue during pregnancy, a mother’s healthcare provider will monitor the levels closely, potentially suggest treatment, and make sure that blood pressure levels quickly return to normal after birth.
- American Pregnancy Association. (2014). Gestational hypertension: pregnancy induced hypertension (PIH). Retrieved from http://americanpregnancy.org/pregnancy-complications/pregnancy-induced-hypertension/.
- BabyCentre Medical Advisory Board. (2013). Blood pressure in pregnancy. BabyCentre. Retrieved from http://www.babycentre.co.uk/a554818/blood-pressure-in-pregnancy#section4
- Planck, Nina. (2009). Real food for mother and baby: the fertility diet, eating for two, and baby’s first foods. Bloomsbury USA: New York.