An observational study in Iron Adverse Reaction and Anemia Complicating Pregnancy, sponsored by Bnai Zion Medical Center. Not yet recruiting at 1 site in Israel. Open to female participants aged 18 Years to 50 Years. Per ClinicalTrials.gov, last updated 2026-01-27.
Sponsored by Bnai Zion Medical Center · Observational
The goal of this prospective observational study is to examine the frequency of gastrointestinal side effects associated with oral iron supplementation during pregnancy. The main question it aims to answer is:
Does intermittent oral iron supplementation result in fewer gastrointestinal side effects compared with daily supplementation in pregnant women? Pregnant women who are prescribed oral iron as part of their routine medical care will take ferrous sulfate on an alternate-day schedule for one week. If no significant gastrointestinal side effects are reported, they will then take ferrous sulfate daily for an additional week and will be followed for one month. Participants will be contacted by the study investigator to report gastrointestinal side effects, and routine blood tests will be used to assess changes in hemoglobin and iron stores.
This prospective observational study will be conducted in pregnant women who are prescribed oral iron supplementation as part of their routine prenatal care. The study is designed to reflect standard clinical practice and does not introduce any investigational treatment or deviation from accepted management.
Following enrollment, participants will receive oral ferrous sulfate in accordance with common clinical recommendations. The study includes two sequential exposure periods: an initial alternate-day dosing phase followed by a daily dosing phase, provided that no significant gastrointestinal intolerance is reported during the first phase.
At baseline, relevant demographic and pregnancy-related information will be recorded, including maternal age and gestational age at initiation of iron therapy. Baseline laboratory values related to iron status (including hemoglobin and iron stores) will be documented if obtained as part of routine care.
Participants will be instructed to take oral iron according to the prescribed schedule and to continue their usual diet and prenatal care. No dietary restrictions will be imposed as part of the study. Information regarding timing of iron intake, concomitant food consumption (including dairy products), and adherence will be collected through participant self-report.
Participants will be contacted by the study investigator at predefined time points during the supplementation period. Structured interviews will be used to assess gastrointestinal side effects, including constipation, abdominal pain, nausea, vomiting, diarrhea, bloating, and heartburn. Participants will be asked whether symptoms are new, worsened, or unchanged compared with baseline.
At one month after initiation of iron supplementation, participants will undergo follow-up blood tests as part of routine clinical monitoring to assess hemoglobin concentration and iron stores.
1,810 studies on the registry are indexed under Anemia; 215 are open to participants now.
This study's planned enrollment of 50 is below the median of 270 across 368 observational studies indexed under Anemia.
Browse Anemia studies →Bnai Zion Medical Center is the lead sponsor of 104 studies on the registry; 13 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Pregnant women attending our high-risk pregnancy clinics (in Bnai Zion medical center)
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Exclusion Criteria:
No intervention. It's an observational study
Incidence of gastrointestinal side effects in response to iron intake
Time frame: Over the first 2 weeks of supplementation, with structured follow-up at week 1 and week 2
Plan to share: No
No publications or documents are linked to this record.
Start is estimated for Feb 2026; primary completion for May 2026, 3 months later.
Of 124 non-industry observational studies under Anemia, half reached primary completion within 30 months of starting (the median), counting those still running; a quarter within 11 and three quarters within 84. This study's planned 3 months is below that.
Counting every sponsor, half of 145 studies reached it within 30 months; a quarter within 12 and three quarters within 76.
How these figures are worked out, and which studies are left out of them.
This study is not yet recruiting, as verified in Dec 2025. You cannot join it, but the record below documents what was studied.
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