Use of high doses of folic acid supplements in pregnant women in Spain: an INMA cohort study

BMJ Open. 2015 Nov 24;5(11):e009202. doi: 10.1136/bmjopen-2015-009202.

Abstract

Objectives: We examined the use of low (<400 μg/day, including no use) and high folic acid supplement (FAS) dosages (≥1000 μg/day) among pregnant women in Spain, and explored factors associated with the use of these non-recommended dosages.

Design: Population-based cohort study.

Setting: Spain.

Participants: We analysed data from 2332 pregnant women of the INMA study, a prospective mother-child cohort study in Spain.

Main outcome measures: We assessed usual dietary folate and the use of FAS from preconception to the 3rd month (first period) and from the 4th to the 7th month (second period), using a validated food frequency questionnaire. We used multinomial logistic regression to estimate relative risk ratios (RRRs).

Results: Over a half of the women used low dosages of FAS in the first and second period while 29% and 17% took high dosages of FAS, respectively. In the first period, tobacco smoking (RRR=1.63), alcohol intake (RRR=1.40), multiparous (RRR=1.44), unplanned pregnancy (RRR=4.20) and previous spontaneous abortion (RRR=0.58, lower use of high FAS dosages among those with previous abortions) were significantly associated with low FAS dosages. Alcohol consumption (RRR=1.42), unplanned pregnancy (RRR=2.66) and previous spontaneous abortion (RRR=0.68) were associated with high dosage use. In the second period, only tobacco smoking was significantly associated with high FAS dosage use (RRR=0.67).

Conclusions: A high proportion of pregnant women did not reach the recommended dosages of FAS in periconception and a considerable proportion also used FAS dosages ≥1000 μg/day. Action should be planned by the Health Care System and health professionals to improve the appropriate periconceptional use of FAS, taking into consideration the associated factors.

Keywords: NUTRITION & DIETETICS; PUBLIC HEALTH.

Publication types

  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abortion, Spontaneous
  • Adolescent
  • Adult
  • Alcohol Drinking
  • Dietary Supplements*
  • Female
  • Folic Acid / administration & dosage*
  • Humans
  • Logistic Models
  • Maternal Nutritional Physiological Phenomena*
  • Odds Ratio
  • Parity
  • Pregnancy
  • Pregnancy, Unplanned
  • Prenatal Care / standards*
  • Prospective Studies
  • Smoking
  • Spain
  • Young Adult

Substances

  • Folic Acid