Microgestin Fe 1.5/30 is a combination birth control pill containing two synthetic hormones: 1.5 mg of norethindrone acetate (a progestin) and 30 mcg of ethinyl estradiol (an estrogen). It comes as a 28-day pack with 21 active hormone pills and 7 non-hormonal pills that contain a small amount of iron. With perfect use, the pill is 99.7% effective at preventing pregnancy. With typical use, which accounts for missed pills and timing errors, that number drops to about 91%.
How the 28-Day Pack Works
Each pack contains 21 yellow active tablets and 7 brown inactive tablets. You take one yellow pill daily for three weeks, then switch to the brown pills for the final week. Your period typically arrives during that fourth week while you’re on the brown tablets.
The brown tablets contain 75 mg of ferrous fumarate, a form of iron. Despite the “Fe” in the name (the chemical symbol for iron), these pills aren’t meant to treat or prevent iron deficiency. They exist purely as placeholders so you stay in the habit of taking a pill every day at the same time. The iron dose is too low to serve a real therapeutic purpose.
How It Prevents Pregnancy
The primary mechanism is straightforward: the hormones stop your ovaries from releasing an egg each month. No egg, no pregnancy. But the pill has backup effects, too. The progestin component thickens your cervical mucus, making it resemble the thick, sperm-hostile mucus your body naturally produces after ovulation. This creates a physical barrier that makes it much harder for sperm to reach an egg even if one were released. The hormones also thin the uterine lining, which makes implantation less likely.
How to Start Taking It
There are two ways to begin your first pack, and the choice affects whether you need backup contraception.
With a Day 1 start, you take your first yellow pill within 24 hours of getting your period. Because you’re syncing with your natural cycle, no backup birth control is needed right away.
With a Sunday start, you take your first pill on the Sunday after your period begins (or that same Sunday if your period starts on a Sunday). This method requires a backup like condoms for the first 7 days, since you may not be starting in sync with your cycle.
Common Side Effects
Microgestin Fe 1.5/30 shares the same side effect profile as other combined oral contraceptives with similar hormone levels. The most frequently reported effects include nausea (especially in the first few months), breast tenderness, headaches, breakthrough bleeding or spotting between periods, and mood changes. These tend to be most noticeable in the first one to three cycles as your body adjusts, and they often ease up on their own.
Some people notice weight changes, bloating, or a decrease in sex drive. Others find that their skin clears up or that their periods become lighter and less painful, which are considered beneficial side effects for many users.
Serious Risks and Who Should Not Take It
Like all combined hormonal contraceptives, Microgestin Fe 1.5/30 carries a small but real risk of blood clots. These can form in the legs (deep vein thrombosis) or travel to the lungs (pulmonary embolism). The risk is low for most people but increases significantly in certain groups.
This pill is contraindicated, meaning it should not be used, if you:
- Smoke and are over 35. This combination dramatically increases the risk of heart attack, stroke, and blood clots.
- Have a history of blood clots in your legs or lungs, even if they resolved.
- Have coronary artery disease or a history of stroke.
- Have or have had breast cancer or other hormone-sensitive cancers.
- Have unexplained vaginal bleeding that hasn’t been evaluated.
- Have liver tumors or severe liver disease, including jaundice triggered by pregnancy or prior pill use.
- Take certain hepatitis C medications containing ombitasvir/paritaprevir/ritonavir, which can cause dangerous elevations in liver enzymes when combined with estrogen.
Medications That Can Reduce Effectiveness
Several types of medication can interfere with how well your body absorbs or processes the hormones in Microgestin Fe 1.5/30. Anti-seizure medications like phenytoin, carbamazepine, and topiramate are among the most common culprits. The antibiotic rifampin (used for tuberculosis) is well known for reducing oral contraceptive effectiveness. Some HIV medications and the herbal supplement St. John’s wort can also lower hormone levels in your blood enough to raise your pregnancy risk. If you’re prescribed any new medication, it’s worth confirming whether it interacts with your birth control.
What to Do If You Miss a Pill
If you miss one active yellow pill, take it as soon as you remember, even if that means taking two pills in one day. You generally don’t need backup contraception for a single missed pill, though some providers recommend it.
If you miss two or more active pills, the situation gets more complicated. The general guidance is to take the most recent missed pill as soon as possible, skip any earlier missed pills, and use backup contraception (like condoms) for at least 7 days. If you missed pills in the third week of your pack, you may be advised to skip the brown pills entirely and start a new pack right away to maintain hormone levels. Missing brown pills during the fourth week doesn’t affect your protection at all, since those tablets contain no hormones.
Microgestin Fe 1.5/30 vs. Other Versions
The “1.5/30” in the name refers to the hormone doses: 1.5 mg of progestin and 30 mcg of estrogen. There’s also a lower-dose version called Microgestin Fe 1/20, which contains 1 mg of norethindrone acetate and 20 mcg of ethinyl estradiol. The lower-dose version may cause fewer estrogen-related side effects like nausea and breast tenderness, but it also leaves less room for error with missed pills. The 1.5/30 formulation is considered a “regular strength” combined pill.
Microgestin Fe 1.5/30 is a generic equivalent of Loestrin Fe 1.5/30. You may also see it dispensed under other generic names like Junel Fe 1.5/30 or Larin Fe 1.5/30. These all contain the same active ingredients at the same doses.