Mar 27, 2026Wearables

Your Wearable HRV Changes With Your Cycle and the Pill

Menstrual phase and hormonal contraception can shift wearable HRV. Learn what progesterone, progestins, and recovery scores can and cannot tell you.

hrvprogesteronemenstrual cycleluteal phase

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Mar 26, 2026Fertility

IVF E2/P Ratio Before Progesterone: Signal, Not a Target

An IVF study of 25,000 HRT-FET cycles links the estradiol-to-progesterone ratio before progesterone to live birth, but weak accuracy limits clinical use.

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Mar 18, 2026Mental Health

How Hormones May Shape Fear Learning—and What the Pill Changes

Estradiol, progesterone, and oral contraceptives may shape fear learning. What human studies say about PTSD risk, safety memory, and uncertainty.

ptsdestradiolfear extinctionoral contraceptives

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Mar 17, 2026Reproductive Health

PFAS and Miscarriage: What the Norwegian Study Found

A large Norwegian study found no measurable PFAS-miscarriage link, yet human hormone data and design limits keep the reproductive health question open.

pfaspregnancymiscarriageprogesterone

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