Hypotension in pregnant women: a population-based case–control study of pregnancy complications and birth outcomes

Abstract

Hypotension is frequent in pregnant women; nevertheless, its association with pregnancy complications and birth outcomes has not been investigated. Thus, the aim of this study was to analyze the possible association of hypotension in pregnant women with pregnancy complications and with the risk for preterm birth, low birthweight and different congenital abnormalities (CAs) in the children of these mothers in the population-based data set of the Hungarian Case-Control Surveillance of CAs, 1980CAs, -1996 Prospectively and medically recorded hypotension was evaluated in 537 pregnant women who later had offspring with CAs (case group) and 1268 pregnant women with hypotension who later delivered newborn infants without CAs (control group); controls were matched to sex and birth week of cases (in the year when cases were born), in addition to residence of mothers. Over half of the pregnant women who had chronic hypotension were treated with pholedrine or ephedrine. Maternal hypotension is protective against preeclampsia; however, hypotensive pregnant women were at higher risk for severe nausea or vomiting, threatened abortion (hemorrhage in early pregnancy) and for anemia. There was no clinically important difference in the rate of preterm births and low birthweight newborns in pregnant women with or without hypotension. The comparison of the rate of maternal hypotension in cases with 23 different CAs and their matched controls did not show a higher risk for CAs (adjusted OR with 95% confidence intervals: 0.66, 0.49-0.84). In conclusion, a higher risk for CAs and other adverse birth outcomes was not found in the offspring of pregnant women with hypotension, but maternal hypotension was associated with a higher risk of some pregnancy complications. Keywords: congenital abnormalities; hypotension; hypotension drugs; pregnancy; pregnancy complications INTRODUCTION Hypertension is a common medical condition that has multiple manifestations, including primary and secondary hypertension disease, preeclampsia and gestational hypertension in pregnant women. 1-3 However, the study of the other end of the blood pressure spectrum (that is, hypotension) has been neglected in pregnant women 4 even though hypotension occurs frequently during pregnancy. We were unable to find controlled epidemiological studies regarding the effect of hypotension and related drug treatments for pregnancy complications or adverse birth outcomes in the medical literature. 5 This medical attitude is partially understandable because hypotension is not a disease; rather, it is a symptom of low blood pressure in individuals and is generally not associated with serious complications.Hypotension occurs frequently in Hungarian pregnant women, and obstetricians, in general after consultation with specialists, prefer to treat the more severe and unpleasant symptomatic manifestations of hypotension during pregnancy. However, the potential teratogenic/

Intradialytic Hypotension and Risk of Cardiovascular Disease

“…Shoji et al found that the lowest intradialytic systolic BP was a significant risk factor for higher mortality and that intradialytic diastolic BP,59 mmHg was associated with a significantly higher risk of death from CV and cerebrovascular disease (7). This effect has also been seen in patients who experience perioperative hypotension (18,19) and peripartum hypotension (20). However, given the alarmingly high prevalence of hypotensive events and the poor underlying CV substrate for many dialysis patients, the relationship between hypotension and mortality may be more important for dialysis patients.…”

Maternal antihypertensive medication use and selected birth defects in the National Birth Defects Prevention Study

“…Combined with the lowering of maternal blood pressure that naturally occurs at the beginning of pregnancy, unintentional hypotension may play a role in impairing fetal development. However, this theory is not supported by limited available evidence (Banhidy, Acs, Puho, & Czeizel, ).…”

Pharmaceutical administration for severe hypertension during pregnancy: Network meta-analysis

“…Two other studies ( Magee et al, 2003 ; Baggio et al, 2011 ) reported that hydralazine could lower blood pressure more than labetalol, leading to a higher incidence of maternal hypotension. However, lowering blood pressure was not advisable because hypotension can impair uteroplacental circulation and increase the risk of severe nausea, vomiting, threatened abortion, and anemia ( Bánhidy et al, 2011 ; Baggio et al, 2011 ).…”