How much prune juice for pregnancy constipation

What does the evidence say about how much prune juice helps constipation during pregnancy?

1. Dried plums carry sorbitol at 14.7 g per 100 g plus polyphenols at 184 mg per 100 g, and sorbitol acts as an osmotic laxative that holds onto water. 1
2. In an 8-week single-blind randomized crossover study of 40 subjects, dried plums at 50 g twice daily (6 g fiber a day) beat psyllium at 11 g twice daily on complete spontaneous bowel movements per week and on stool consistency. 1
3. Plums and prune juice are effective for constipation, more so than psyllium, and their effect may be due to their fibre and sorbitol content. 2
4. Adults should get 22 to 34 grams of fiber a day and drink plenty of water and other liquids when increasing fiber, with osmotic agents like polyethylene glycol working by increasing fluid in the digestive tract. 3
5. Iron supplements are a common driver of the problem in pregnancy: the pregnancy RDA is 27 mg a day, and high-dose iron brings constipation, nausea, and gastric upset. 4

Is how much prune juice helps constipation safe in each trimester?

• First trimester. Constipation often arrives alongside prenatal iron, and iron supplements are known for constipation and gastric upset. Adding fiber and fluid before adding a laxative is the usual order, and prunes sit in the fiber category.
• Second trimester. This is a good stretch to work on the baseline rather than the rescue: NIDDK puts adult fiber at 22 to 34 grams a day, and the constipation literature adds at least eight glasses, roughly 1.5 to 2 litres, of fluid daily.
• Third trimester. Pressure makes everything slower now. The trial that beat psyllium used 50 g of dried plums twice a day for three weeks, which is a steady habit rather than a single big glass when things get stuck.

What was actually studied, and in whom