This post, written by Amy Babchek from the Nike Foundation, originally appeared on the Girl Effect website and is available here.

Girls are finally on the agenda for family planning pledges, but misinformation about their needs and behavior stops girls getting access to the advice and resources they need for family planning. Amy Babcheck from the Nike Foundation is myth-busting.

At this year’s London Summit on Family Planning, global leaders pledged funds and resources for an additional 120 million women and girls by 2020. That’s right—girls. Adolescent girls and young women represent 26 million, or 20 percent, of that total, and that’s a major breakthrough.

Adolescent girls and young women in developing countries haven’t always been included when it comes to meeting family planning needs. Why? Because they become entangled in religious, political and cultural arguments, many of which are myths, yet still widely believed. Here are some of the worst…

MYTH: The world knows a lot about the situation of adolescent girls under the age of 15 when it comes to early sexual activity and early childbearing.

TRUTH: Publicly available information on the situation of very young adolescent girls ages 10-14 years is limited. Yet we know from secondary analysis that in 14 sub-Saharan African countries, 15 percent or more of girls reported having sex before their 15th birthday. And that’s just those who reported—the number is likely to be higher. A substantial proportion of sexual encounters involving very young adolescents are forced or coerced.

Want more details? Investing when it counts

MYTH: Adolescent girls understand their body, menstrual cycle, conception and contraception.

TRUTH: Cultural barriers make correct information about puberty and reproductive health and contraceptives inaccessible. Girls often feel shame and humiliation about their menstrual cycle, so even when they do know where or whom to ask questions, they don’t. This also affects their contraceptive use and ability to plan pregnancy. Because adolescent girls don’t understand their body well, they also don’t understand how they become pregnant or how to prevent pregnancy.

Want more details? Charting the future; Girls decide: choices on sex and pregnancy

MYTH: Adolescent girls who have correct information about and access to family planning (contraception) begin having sex earlier, and have more partners.

TRUTH: Girls who have access to information and contraception have a later age at sexual debut, are less likely to experience coerced sex (if they have built social assets), and are more likely to use contraception when they do have sex.

Want more details? Start with a girl: a new agenda for global health

MYTH (that we often hear from girls): Contraception makes girls infertile, gain weight, grow facial hair and/or get cancer.

TRUTH: Most contraception has no effect on girls’ fertility; some medically intensive methods (such as IUD, implants, etc.) need to be properly administered by a trained medical provider to be safe for girls and women.

Want more details? World Contraception Day: myths, rumours and rubbish

MYTH: All modern contraceptive methods work for adolescent girls.

TRUTH: Permanent sterilization is not an option. And girls want contraceptive methods that they can control, that they can keep very private and that are longer acting —but not permanent. Sex for girls is often out of their control, and when they can’t negotiate condom use to protect them from disease, they at least want to be protected from unwanted pregnancy. Girls don’t want to be seen acquiring or using contraceptives because, whether married or not, using contraceptives goes against cultural norms (girls shouldn’t have sex out of wedlock and should want babies once they are married). Girls often don’t have the means to regularly acquire contraceptives.

Want more details? Start with a girl: a new agenda for global health

MYTH: Girls who do access contraceptives are adequately informed about how to use them.

TRUTH: Girls often have misinformation or misunderstanding about how to properly use contraceptive methods, with the pill being among the most misunderstood.

Want more details? Facts on the sexual and reproductive health of adolescent women in the developing world

Commit your resources to girls and young women, the untapped accelerators of economic development, and by 2020 you will have unleashed the girl effect through access to contraceptives and family planning.